1. Field of the Invention
The present invention relates to a user interface in a hands-free terminal. For instance, the present invention relates to a hands-free terminal used in a state mounted on a car or another vehicle.
2. Background Art
Presently, for the sake of communication during driving a car, a hands-free phone allowing a driver to communicate without holding a handset (cell phone) has been developed and come onto the market. In a typical hands-free phone, a microphone is disposed at a position apart from the mouth of a user in communication (driver). Accordingly, the hands-free phone internally executes a signal processing for eliminating noise input into a microphone together with a communication speech (sound unnecessary for a communication speech, such as noise during driving).
However, the signal processing also affects the communication speech. More specifically, the signal processing causes a side effect, such as deterioration in quality of communication speech. Thus, in a development stage, the contents of signal processings capable of reducing noise as much as possible while reducing the side effect as much as possible are typically discussed, and products to which only setting contents determined as optimum are applied are shipped.
However, in actuality, the optimal setting content is largely different according to the loudness and type of the voice of the user in communication, the type and loudness of noise and the like. Thus, a technique to which a plurality of setting values are preliminarily installed in the hands-free phone to allow optimal setting values to be selected for respective occasions have conventionally been proposed.
For instance, a hands-free phone at which a user in communication himself/herself can select a setting value to be applied in response to the occasion has been proposed. Further, for instance, a hands-free phone having a function of automatically selecting a setting value to be applied by the device in response to loudness of speech and noise at the occasion.
However, it can be considered that most of situations are a case where the voice of a user in communication is low, a case where a window of the car is open, the air conditioning function is in use and the like. In these situations, it can be considered that, without changing the setting of the signal processing, it is effective, in increasing communication quality, that the user in communication speaks more loudly, closes the window, or stops the air conditioner. Thus, a mechanism of feeding the current communication quality back to the user has been discussed.
JP Patent Publication (Kokai) No. 2008-211670 A (2008) discloses a mechanism that notifies a user of the transmission quality of the currently used line in an IP (Internet Protocol) phone. This document provides a mechanism of allowing the user to easily grasp communication situations by presenting the user with an objective indicator for evaluating the line quality.
JP Patent Publication (Kokai) No. 2008-211361 A (2008) discloses a technique that presents the user with communication situations, considering a cell phone as a target.
JP Patent Publication (Kokai) No. 2007-329630 A (2007) has the same object as JP Patent Publication (Kokai) No. 2008-211670 A (2008), but discloses a technique that presents a user with an amount of echo of a communication speech. JP Patent Publication (Kokai) No. 2007-329630 A (2007) is capable of presenting a user with an actual quality of a communication speech, which is different from JP Patent Publication (Kokai) No. 2008-211670 A (2008).
The current communication quality (line quality, and speech quality) can certainly be presented to a user using techniques disclosed in JP Patent Publication (Kokai) Nos. 2008-211670 A (2008), 2008-211361 A (2008) and 2007-329630 A (2007). However, even with use of these techniques, actions to be taken by the user to increase the communication quality cannot be realized. In the first place, it is difficult to change the communication quality by users' measures in typical fixed-line phones (IP phones) and cell phones assumed in JP Patent Publication (Kokai) Nos. 2008-211670 A (2008), 2008-211361 A (2008) and 2007-329630 A (2007).
In contrast, in a case where effects of communication environment on communication quality are large as in a hands-free phone used in a car, the quality of communication speech can relatively easily be improved by the user performing actions such as speaking loudly and closing the window.